Hydraulic classifier



April 15 1924. 1,490,420

r R. B. ELDER HYDRAULIC CLASSIFIER F l J ne. 20; 1 1 5 S aw-Sh t 3 3Sheets-Sheet 2 April 15 1924,

R. B. ELDER HYDRAULIC CLASSIFIER Filed June 20, 1918 ATTORNEYS g, m 4 mm a? W 4 J F 7 I 2 a a o c v n/ 0 IM "m m 9 lxll) 0 0 b u p u 9 T w nd.m z z 5 m w @v Q m 4 u 4 flaw n n 5 m WITNESSES WWW April 15 1924.

R. B. ELDER HYDRAULIC cLAss-IFIER 3 Sheets-Sheet 5 Filed June 20 1918WITNESSES 94 A TTORNEYS t atented Apr, 3%, 392%,

ataata RQBERT BAXTER ELDER, 0E UNSANKINKO, CHOSEN, JAPAN, ASSIGNOR 1'0ANDREW DARWIN ELDER, 01 DENVER, COLORADO.

HYDRAULIC CLASSIFIER.

Application filed June 20,

To all whom it may concern Be it known that I, Ronna'r BAXTER ELDER, acitizen of the United States, and a resident of UnsankinkoyChosem,Japan, have invented certain new and useful Improvements in HydraulicClassifiers, of which the following is a specification.

My invention is an improvement in hydraulic classifiers, and has for itsobject to provide a device ofthe character specified, wherein a teeterchamber is provided, arranged above hydraulic and discharge chambers,the latter communicating with the teeter chamber by arestricted openingand the former by. a number of openings, and wherein a stand pipe havingan overflow is provided-in connection with the discharge chamber.

A further-object is to provide a means for introducing water into ateeter chamber in such a manner as to maintain even distribution of thewater to all portions of the teeter chamber and so to prevent theformation of banks of sand in any portion thereofland to maintain auniform liquid bed of pulp over the entire teeter chamber area.

A further object is to provide a simple means for regulating the flow ofwater to the teeter chamber so that the regulation may be made andestablished correctly and thereafter will not be dependent on thejudgment or guess of operating attendants.

A further object is to provide a device of the character specifiedwherein the discharge of the heavy classified pulp from the teeterchamber depends on the thickness and density of the bed of pulp in theteeter chamber.

In the drawings:

Figure 1 is a longitudinal section, showing the improvement applied to asingle pocket classifier of the launder type;

Figure '2 is a section on the line 2-2 of Figure 1;

Figure 3 is a vertical section of the improvement applied as a coneclassifier;

Figure 4 is a longitudinal section showing the improvement.applied as a.four spigot classifier;

Figure 5 is a front view of another embodiment of the invention;

1918. Serial No. 240,997.

Figure 6 is av plan view;

Figures 7, 8 and 9 are sections on the lines 7-7, 88 and 9-9,respectively, of Fig ure 6;

Figure 10 is a section on the-line 10.10 of Figure 5.

In the embodiment of the invention shown in Figures 1 and 2, acasing isprovided having its enclosing walls at the bottom perpendicular, asindicated at 1, and flaring above the perpendicular portion, asindicated at 2, where they connect with the launder 3. A partition 4 isarranged in the bottom of the casing, the said partition incliningdownwardly from the inlet toward the outlet end of the casing, andthesaid partition is between the perpendicular walls of the casing.

Another partition 5 is arranged between the partition 4 and the bottomof the cas-. ing at the outlet end of the casing, and this partition 5divides that portion of the casmg below the partition 4 into twochambers, a iydraulic chamber 6 and a discharge chamber 7, and adelivery valve or spigot 8 leads from the discharge chamber. Thisdischarge chamber communicates with the space in the casing above thepartition which is the pulp chamber, and a series of openings 9 isprovided in the partition 4 for furnishing a means of communicationbetween the hydraulic chamber and the pulp chamber.

Drain valves 10 are provided in the bottom of the casing for drainingthe hydraulic chamber, and water is furnished to the chamber by a pipe11 which is controlled by a valve 12. A stand pipe 13 is provided at oneside of the casing, the said pipe extending from the bottom of thecasing to above the top of the launder, the bottom of this pipe beingconnected with the discharge chamber, as shown, and this pipe has adischarge opening 14; above the pulp level through. which the water mayflow on to the pulp in the launder. A pipe 15 communicates with thebottom of the stand pipe by means of which water may be supplied to thepipe to maintain the water level at the overflow opening 14, and a valve16 is arranged in the pipe forcontrollin the same.

In the embodiment of the invention shown in Figure 3 the casing has theportion 17 with perpendicular walls and the portion 18 with flaringwalls, and the overflow 5 launder 19 is arranged near the top of thecasing in a manner to receive the overflow from the casing. A feed cone20 is arranged centrally of the casing at the top, and the stand pipe 21extends upwardly from near the bottom of the casing to above the top ofthe feed cone. Here the stand pipe is provided with a discharge spout 22discharging into the cone, and with a supply ipe 23 for maintaining thelevel of water 1n the stand pipe. This pipe 23 is controlled by a valve24 and the pulp is fed to the feed cone by a feed launder 25. Apartition 26 is arranged near the bottom of the casing the saidpartition dividing the casing into an upper teeter chamber and a lowerportion which is sub-divided by partition 27 into a hydraulic chamberand a dischage chamber, the lower end of the stand pipe communicatingwith the discharge chamber. The partition 26 inclines downwardly towardthe center of the casing, and it is provided with openings 28 forming acommunicationbetween the teeter chamber and the hydraulic chamber. Thedischarge chamber communicates with the teeter chamber and a dischargevalve 29 leads from the discharge chamber. Drain valves 30 are pro"vided in the'hyd'raulic chamber, and water is supplied by means of apipe 31. ,Intheenibo'dimentof the invention. shown Figure githe casinghas the portion 31 lwithfverticali wallsa nd the portion 32' with fling-walls which connect with the launder 33.,;

jflhelowerportion ofthe casing is difvid ed'fby verticalp a'rtitions 34into four fpocketaandan inclined partition 35 sepal rates eachpocketinto a lower portion and Fan upper portion. These partitions 35incline downwardly toward the discharge end off the casing-fend a.partition 36 separates each lower portion into a hydraulic chamberand-a discharge chamber. The partitions 35 have openings 37correspcinding to the open-' ings 9 and 28, and a discharge valve 38leads from each discharge chamber. Each hy-- draulic chamber has-Ldrainvalves 39, and a standpipe 40 leads upwardly from each (lischargechamber to abovethe level of the top of the launder. These stand pipes405have overflow outlets 41' corres onding to the outlets 14 and22, andit will be noticed from an inspection of Figure 4 that the said openingsare of lessheight above the bottom of the casing at the discharge end ofthe launder than at the inlet end, that is, the stand pipe 40 at theinletv end has its overflow opening at alhigher level than the remainmgopenings, and they are gradually stepped downwardlyirom the inlet to theOutlet end of the casing.

Water is supplied by a water pip: 42 to the hydraulic chambers, eachcham I having its supplyinpedendent of the other chamber.

The operation of all. of the embodiments is the same, each being ahindered settlin hydraulic classifier, for classifying crushed ore,preparatory to treating it on Wilfley tables or other concentratorsdesigned to separate the valuble minerals from the gangue. The deviceconsists essentially of the following parts, namely, a teeter chams berwherein the ore pulp is thickened to a condition of hindered settling,and this condition maintained; second, means for bringingtheunclassified pulp over the teeter chamber in order that the oreparticles may have a chance to sink into the teetering mass or becrowded out by heavier articles, as the case may be, with means fidrcarryin away the lighter portions of the pulp whicl i could not sinkinto the teeter chamber; third, means for introducing hydraulic waterinto the teeter chamber through small holes in the bottom thereof and insuch a way as to maintain uniform hindered settling conditions over theentire area of the teeter chamber, and as not to allow parti- 0185 ofore to settle out of the teeter chamber against the incoming hydraulicwater; fourth, means for discharging the heavy classified pulp from theteeter chamber, at

or near the bottom, and into a discharge chamber wherein the hydrostaticpressure is regulated independently of the hydraulic water which doesthe classifying; fifth, means for. maintaining constant or nearly so thehydraulic pressure in the discharge chamber; and, sixth, means forintroducing water into the discharge chamber and independently of thewater introduced into the teeter chamber.

The problem of making a successful hindered settling classifier may beresolved into two parts; first, to produce and maintain uniform hinderedsettling conditions over the entire teeter chamber area; second, todischarge the products of classification separate from each other and asfast as they are formed.

In order that there may be uniform hindered settling conditions over theentire area of the teeter chamber it is necessary that there be a slowlyupward moving current of water uniform or nearly so over the entirearea. The hydraulic water enters the teeter chamber from the hydraulicchamber through the constriction openings 9, 28 and 37 in the partitionwhich separates these chambers, and a it enters the teeter chamber it isin the form of jets.

spread out as the water' moves upward and mingles with the'pulp, and theresult is that a short distance above the bottom of the teeter chamberthe hydraulic water is These jets diflused uniformly into the pulp andforms the desired slowly upward moving current of water practicallyuniform over the enthe water in the jets. The nearer the holes areplaced and the smaller the velocity of the incoming water the less depthis re-' quired for thedifi'usion to take place.

The essential function of the constriction plate or partition whichseparates the teeter and hydraulic chambers is to maintain the evendistribution of the hydraulic water over the teeter chamber area. Thisit does by ofi'ering tothe flow of hydraulic water such a reslstancethat the inequalities tending to form in the weight of thepulp bed atdifierent points have no appreciable effeet on the flow of water. Thebed just over and adjacent to the point where the heavy classifiedmaterial is discharged from the teeter chamber tends to become lightersince here it is continuously removed, and the bed just under the pointwhere'theunclassified pulp is fed to the teeter chamber tends to becomeheavier, as heavy ore particles are continuously added at this point. Inpassing from the hydraulic water chamher to the topof the pulp bed thehydraulic water meets with resistancefirst from the constriction plateand then from the pulp bed. The resistance offered by the constric tionplate must be great enough so that slight variations in the resistanceoiiered at different points in the pulp bed do not materially efiect thedistribution of water over the teeter chamber area, and at ,the sametimeit must not be so great that the velocity of the incoming jets is sogreat as to require "an undue depth in the pulp bed before they becomedifiused into the pulp. When the resistance offered by the constrictionplate is great enough to maintain the proper distribution of i thehydraulic water, as described, the velocity of the incoming jets ofwater will be great enough so that no ore particle can settle throughthe constriction openingsagainst the entering current of water.

The discharge of the heavy classified pulp is regulated by controllingthe hydraulic pressure in the discharge chamber. In practice,ifsuflicient water is permitted to flow;

into the discharge chamber, so that a little overflows the top of thestanding column or stand pipe the hydraulic pressure will bemaintained-practically constant at the opening between the teeterchamber and-tthe discharge chamber and will be fixed by the height ofthe column of water. The cross sectional area of the column and itsconnection must be large enough so that the friction head of a smallamount of water passing through them will be negligible.

. The height of the overflow of the column is then made such that thehydraulic pressure maintained at the opening between the teeter anddischarge chambers is equal to the hydraulic pressure due to a column ofpulp, the height of the teeter chamber and of the density desired to bemaintained in the teeter chamber plus the column of less dense pulpabove'the top of the teeter chamber. The density of the pulp above thetop of the teeter chamber will remain practically constant, so that itis evident that under the conditions described, whether there is amovement of liquid from the discharge chamber into the teeter chamber orin the opposite direction will depend on the density of the pulp in theteeter chamber. If this density exceeds the amount necessary to balancethe constant hydraulic pressure in the discharge chamber. there will bea movement from the teeter chamber into the discharge chamber. Themovement from the teeter chamber into the discharge chamber will thinthe pulp in the teeter chamber until equilibrium is again restored. Themovement of the water into the teeter chamber from the discharge chamberwill hinder the particles from leaving'the teeter chamber so that thedensity of the pulp in the teeter chamber will be thereby increased, andthis Will continue untilequilibrium is again restored. In this way thedensity of the pulp in the teeter chamber will be kept practicallyconstant, rovided only that the area of the opening etween the teeterand the discharge chambers is equal to or less than the area throughwhich the coarse ore particles in the pulp being treated will passsimply by free settling, and without a move-- ment of liquid either way,and provided, also, that this opening is not so small'but what a slightincrease of density of the pulp will produce movement enough todischarge the pulp as fast as it is formed by the ore particles fed tothe teeter chamber.

In practice, the area of this opening, that is, the opening between theteeter and discharge chambers,-should be something less than the areawhich will discharge the particles b-y freesettling, say, for instance,half such area. Then the density of the pulp in the teeter chamber willincrease until a steady stream of pulp is discharged into the dischargechamber, at a velocity equal to twice the average, free. settlingvelocity of the particles; In' this way the -machine will IOU providedthat the area of the teeter chamber is large enough for the overload.

Echarge chamber if there is the proper density of pulp in the teeterchamber. If this density exceeds the amount necessary to bal- .ance thepressure in the discharge chamber there will be movement from the teeterchamber into the discharge chamber, while if the density is less thanthe amount necessary to balance the pressure in the discharge chamberthere willl be movement in the opposite direction. From the dischargechamber the pulp passes through the valves 8, 29 and .38 for furthertreatment.

The embodiment of the invention shown in Figures 5 to 10, inclusive, ischaracterized by the addition of a feed water chamber arranged above theclassifier and from which all the water used by the classifier isderived. In the said embodiment of the invention two discharge chambers50 and'51 are provided, separated from a partition 52, and thechamberrated from the waste chamber 53 tion 54 and from the chamber 51 issepaby a parti- 53 leads a waste pipe 55. The water is fed into thefeedwater chamber 56 which is above the discharge chambers, and to whichwater is delivered from a pipe 57 having a valve 58 for controlling theflow of the water.

'Spigots 59 lead from the feed water cham-' her and deliver to pipes 60,which pass downward through the discharge chambers, delivering to thehydraulic chambers 61, one of which is arranged beneath each pulp orteeter chamber 62, of which there are two,

corresponding to the number of discharge,

chambers and number of hydraulic chambers. Each teeter or pulp chamber'62 is separated from the ad acent hydraulic chamber by a partition 63having openings for permitting the water to flow from the hydraulicchamber to the teeter or pulp .chamber. The excess water from the feedchamber 56 over and above that passing through the spigots 59, flowsover the end 64 of the feed water chamber into a passage 65, which opensintoa passage 66 communicating with the discharge chamber 50 through anopening 67. Each discharge column or chamber communicates with theadjacentpulp chamber through an opening 68, whose extent may be variedby means of a valve or gate 69, mounted to'slide in guides-7O on thechamber wall. These'ports or openeach other by I ings 68 are adjacent'tothe pipes which lead the feed water from the spigots to the hydraulicchambers. A screen 71 is arranged between the feed water chamber properand the spigots, to prevent the pas.- sage of sediment. Spigots 72 leadfrom the bottom of the discharge chambers 50 and 51 to deliver the pulp,and each hydraulic chamber is provided with a drain pipe 73,

which can pass through the spigots 59, and

the. excess flows ever the the passages 65 and 67 into the firstdischargechamber 50. The chamber 50 is the discharge column anddispartition 64 through charge chamber regulating the dischar' e of pulpfrom the first or adjacent teeter c 1amthis discharge ber 62. Theoverflow from column or chamber is by way of the parti tion 52separating the discharge chambers,

66 and the openingand the chamber 51 is the discharge column of thesecond teeterchamber. The water coming through the; opening 67 supplieswhat is needed for the spigot 72 of the chamber 50, the excess of wateroverflowing the partition 52, as above stated, for supplying the spigot72 of the chamber 51, from which flows the pulp delivered by the saidchamber 51 from the second teeter chamber 62. The final execess of wateroverflows the partition 54 and runs to waste through the pipe 55.

The essential function of the feed water chamber'56 and the spigots 59leading there from is to furnish a means whereby the amount of waterrunning to the teeter chambers may be accurately adjusted ,to thecorrect amount when the classifier is first put into use, and thisamount of water may thereafter be continuously furnished to each teeterchamber without the necessity for readjusting the Water except to seethat the required level of water is maintained in the feed waterchamber. In the construction which I show, the level ofthe water in thefeed water chamber is maintained at the desired point by providingthefeed water chamber with an overflow, but it is obvious that any meansfor maintaining this water level would be equally as effective, as, forinstance, a feed water chamber having no overflow and having the valve58 controlled by a float in the chamber 56, so that ias the water in thesaid chamber 56 would be maintained at a constant level. With thisconstruction another water supply for the discharge chambers 50 and 51would be providedI' This construction would not be a departure from thespirit of my invention, but I prefer the construction which I show inthe drawings as it requires only one water supply.

It will be noticed that the top of the pipe 60 is high enough above thelevel of the pulp-in the pulp chambers, which is indicated by the dottedlines oi. Figures 9 and 10, so that the water may rise in the said pipehigh enough to force itself into the teeter chamber against any bed ofpulp which can form therein, and this insures at all times a constantfeed of Water to do the classifying, the amount being determined by thesize of the spigots 59 and the head of water maintained in the feedwater chamber, and independent of the density of the pulp bed in theteeter chambers. The screen '71 prevents any solid matter from findingteeter chamber are its way into the sp-igots and thence to the hydraulicWater chambers, where" it might stop the restricted openings in thepartition 63.

In use, the unclassified pulp is fed into the extension 77 at the frontof the classifier, from whence it fiows into" the first teeter chamber62. The pulp rejected by thefirst teeter chamber flows to the secondteeter chamber, passing over the partition 7 8 which separates the twochambers, and the lightest particles which are rejected by the secondcontained in the pulp which flows over the partition 79 between thesecond pulp chamber and the outlet 82.

ll claim:

1. A device of the character specified, comprising a casing, an inclinedtransverse partition near the bottom of the casing, an approximatelyvertical partition between the transverse partition and the bottom, saidpartitions dividing the easing into an uper ulp or teeter chamber andlower hyrau ic and discharge chambers, means for supplying water underpressure to the hydraulic cham er, a discharge valve for the dischargechamber, a stand pipe communicating with the dischargephamber andextending above the discharge chamber commimicating with thepulp chamberby arestricted opening, the i inclined transverse partition havingopenthe pulp level'in the pulp chamber and having an overflow above thesaid level,

the pulp chamber and communicating with the hydraulic chamber.

3. In a device of the character described,

a teeter chamber, a hydraulic chamber there beneath and separatedtherefrom by a partition through which highly restricted openings areformed, means for supplying water through the partition to the teeterchamber in such a quantity that a predetermined pressure head may bemaintained across the partition to effect even distribution of the waterto all parts of the teeter chamber, means for supplying unclassifiedpulp to the teeter chamber, means for regulating the discharge ofclassified pulp therefrom and means controlled by'the changing of pulpdensity for regulating the discharge of pulp from the teeter chamber. I

4. In a device of the character described, a teeter chamber in all partsof which a unitormhindered settling bed of pulp is maintained by waterentering the teeter chamber through numerous restricted openings in thebottom thereof and under sufiicient pressure to overcome the tendency ofthe pulp to form a bank or solid mass upon the bottom of the teeterchamber, and means in connection therewith and controlled by thechanging of the pulp ,densit whereby the discharge of the heavy classied portion of the pulp will be effected.

5. In a device of the character specified, a teeter chamber, means forsupplying hydraulic'water to produce hindered settling classificationtherein, means for maintaining the even distribution of the h draulicwater over the teeter chamber area y forcing it to enter the teeterchamber through numerous small openings distributed over the bottom ofthe tester chamber, the said openings being so restricted that theyformenough resistance to the passage of the water that the distributionof thewater is thereby maintained regardless of slight inequalities inthe weight of the pulp bed at different points in the teeter chamber,and means in connection therewith. and controlled by the changing of thepulp density for regulating the discharge of the heavy classifiedportion of the pulp therefrom. A

6. In a device of thecharacter specified, a teeter chamber, a dischargechamber with which the teeter chamber communicates by a restrictedopening, means for supplying water under pressure to the bottom/of theteeter chamber to produce hindered settling classification therein, astand pipe commu nicating with the discharge chamber and extending abovethe pulp level in the pulp chamber and having an overflow above the pulplevel, and means for removing the heavy classified material chamberotherwise than nicating therewith by of the first teeter chamber, eachdischarge column having an overflow leading to the succeeding dischargecolumn.

8. In a device of the character specified, apulp or teeter chamber, ahydraulic chamber below the pulp chamber and communieating therewith brestricted openings, a

dischar e column a jacent to the pulp chamber an having a restrictedcommunication therewith, a feed water chamber above the discharge columndischarge chamber and communicating with the hydraulic chamber, the feedwater'chamher having an overflow leading to the dischar e column.

9. n a device-of the character specified, a pulp or teeter chamber, ahydraulic chamber below the pulp chamber and communicating therewith byrestricted openings, 9. adjacent to the teeter chamber and having avalved communication therewith, a feed water chamber above the dischargechamber and communicating with the hydraulic chamber, the feed waterchamber having an overflow leading to the discharge column.

10. A device of the character specified, comprising a casing having an nper pulp chamber and lower discharge and ydraulic chambers communicatingwith the pulp chamber, means for supplying water under pressure to thehydraulic chamber, a stand pipe communicating with the discharge chamblevel of the pulp in the pul chamber and filled to this overflow levewith nearly static clear water. and means the classified pulp from thedischarge chamber otherwise than through the stand 11. In a device ofthe character-specified,

- a teeter chamber, a hydraulic chamber beneath the teeter chamber andcommunicating therewith by restricted opemngs, means for supplying waterunder pressure to the hydraulic chamber, a discharge chamber chambercommuniproducing in the discharge chamber at the discharge opening aconstant hydrostatic pressure-greater than that of a column of er,having an overflow level above the for removing ht to the. vertical argeopenin and pulp in the teeter 0 am clear water equal in hei distancebetween the disc the surface of the her.

12. In a hvdraulic classifier, a pulp chamber provide(. with feed andoverflow means and a perforated bottom, a hydraulic chamber communicatinwith the pulp chamber through vided with awater feed, a dischargechamber in direct communication with said pulp chamber adjacent saidperforated bottom a pressure column in communication w1th saiddischarage chamber and rovided with an overflow above the level of theoverflow of the pulp chamber, and a water feed to said pressure columnindependent of the water feed to' said hydraulic chamber.

13. In a hydraulic classifier, a ulp chamber provided with feed and overow means, a hydraulic chamber communicatin with the pulp chamber througha plur ity of' smallapertures in the bottom chamber, a discharge chamberin communication with the pulp chamber adjacent its bottom, a pressurecolumn in communication with the discharge chamber and provided with anoverflow above the level of the overflow in the pulp chamber, andindependent water feeds to the hydraulic chamber and to the dischargechamber pressure column.

14. In a hydraulic classi of pulp chambers, each pro 'ded with feed andoverflow means and a perforated bot tom and a hydraulic chamber on theother side of the said perforated bottom provided with water feed, .adischarge chamber in communication with each pulp chamber a of the pulper, a plurality pressfire column in communication t with each dischargechamber and provided with an overflow above the level of the overflow ofits pulp chamber, and water feed means to the pressure columnindependentof the water feed to the hydraulic chamber.

15. In a hydraulic classifier, a pulp chamber provided with feed andoverflow means and a perforated bottom, a'hydraulic chamber on the otherside tom and pulp chamber, a pressure column in communication with thedischarge chamber and ROBERT BAXTER ELDER.

' Witnesses:

A. 0.. Emma, Sm Pom; Hm.

said per orated bottom, and pro-.

I of the perforated botprovided with water feed, a discharge chamber incommunication withtheprovided with an overflow above the level "of" thepulp chamber overflow, and water means .to the pressure column mde-

